Is there a way to remove corrosion from aluminum without damaging the metal? I have a 2500 series passenger car with some corrosion on the roof, and I’d like to remove it. I have a Dremel tool, but I wasn’t sure of which bit I should use.
Jim,
I noticed that corrosion in some of the photos you sent me. Try this. Get a wide finger nail file that is medium course on one side, not as course on the other. Start with the courser side and file the aluminum until the corrosion is gone. Finish with the smoother side. Feather the filing out across the top of the car. Don’t use the Dremel. Due to the drum shape, you risk making an indentation in the aluminum. The files are flat and won’t do that.
Use folded sandpaper to remove the corrosion from between the fins. Use your discretion and common sense to figure out how course the paper should be. Rule of thumb for me is, start with medium to smooth. You can always go to a courser grit if need be.
Jim
Jim,
Thanks for the reply. I bought some Mothers Mag and Aluminum polish this week, so I am going to clean these cars up a bit.
One more thing, Jim. Wear a dust mask when you file or sand that aluminum. Better safe than sorry.
Jim
Actually Dremel sells wire brushes specifically for soft metals. You need a Dremel that is variable speed and you shouldn’t have a problem. Like Jim said, wear a dust mask, eye protection, and do this outside. Set the Dremel at the lowest setting and go to work, do not focus on one area too long.
That’s the same stuff I use. The paste that is. I use a tooth brush to buff the corrugations. For stubborn corrosion, a cloth over my thumb nail. For real stubborn corrosion, aluminum mag etching spray. You have to be careful with that and seal it with liquid aluminum polishing compound.
Brent,
I have a brass wire wheel, but I think I’ll try the sandpaper first.
John,
Thanks for the tip. I was wondering how I could get into the ribs with the polish.
I use Mother’s Mag Wheel polish as well, and did exactly as John does with a toothbrush. Don’t let the polish dry. I found the best method was to disassemble the entire car so I was just working on the aluminum shell. After polishing, there were still some residue between the fins, no matter how much I tried to remove it, so I rinsed the shell under a faucet while using a toothbrush. Worked great! Toothpicks also work well for removing residue.
Those finger nail files are also great for removing scratches in the aluminum fins. I had a ton of them. Most sanded out smooth.
DO NOT use a brass wire wheel!!! It will turn the aluminum brass-colored! Don’t use a steel wire wheel because it will leave pieces that can rust and stain the aluminum. A stainless steel wire wheel can be used safely on aluminum (with proper eye protection).
Best of luck, Jim.
Yes, I forgot to mention getting it off. I do it the same way Jumijo does with a toothbrush under running water and Dawn (one of the few detergents that don’t leave a film). Disassembling the car is easy and protects the silhouette window strips.
A good general rule any time you’re working with unpainted metals is to not use a tool that’s made from a different metal than what you’re working with. So don’t use a steel wire wheel on brass, or a brass wheel on aluminum, etc. Particles from the tool can contaminate the surface of your metal.
There are exceptions to the rule, but if you’re not sure, better safe than sorry.
Yes, non ferrous metals such as aluminum will draw carbon out of steel and stain the aluminum. The green and white powdery ring you sometimes see around brazed copper fitting joints is from the plumber using steel fitting brushes. Stainless brushes prevent that.
I’d like to thank everyone for their replies. I polished the 2532 this morning, and it came out great. I never realized that it could be so shiny. How do I get the toof assembly off of the 2531 observation?
How did you do with the corrosion, Jim?
That is right. Get down and dirty with some sand paper and good ole elbow grease.
Jim,
I lightly touched the brass wire wheel to it, and the corrosion was gone with no ill effects on the aluminum. I’ll get pics poste here soon. I wanted to yesterday, but I had to take the Christmas layout down, then I replaced the instrument cluster in the Sunfire. That was a project. I had to take the entire dash out.